Method of producing toner

Abstract

Provided is a method of producing a toner including the steps of: mixing a resin solution comprising a resin R, a colorant, and an organic solvent, a resin fine particle comprising a resin S containing an element α, and carbon dioxide to form a droplet having a surface covered with the resin fine particle; introducing carbon dioxide in a liquid state and pressurizing to extract the organic solvent in the droplet; and removing the extracted organic solvent together with the carbon dioxide to provide a toner particle. In the method of producing a toner, when the resin fine particle is treated with the carbon dioxide in a liquid state, a change in amount of the element α on the surface of the resin fine particle after the treatment as compared to the amount before the treatment falls within a specific range.

Description

BACKGROUND OF THE INVENTION[0001]Field of the Invention[0002]The present invention relates to a resin fine particle and a method of producing a resin particle including using the resin fine particle, and more particularly, to a method of producing a toner to be used in a recording method involving utilizing an electrophotographic method, an electrostatic recording method, and a toner jet type recording method.[0003]Description of the Related Art[0004]Resin particles have been utilized as powder having a high function in a wide variety of fields, and monodisperse resin particles having a narrow particle size distribution have been required in many cases in order to control the function. Particularly in the field of electrophotography, the particles of a toner forming an image need to have uniform performance because the particles has a significant influence on an improvement in quality of the image. To that end, the uniformization of the particle diameters of the toner particles to s...

AI Technical Summary

Benefits of technology

[0017]The present invention has been made in view of such problems as described above, and the present invention is directed to providing a resin fine particle that is available at a low cost and is used for obtaining resin particles and a toner having sharp particle size distributions and high circularities. Another object of the present invention is to provide methods of producing a resin particle and a toner each involving using the resin fine particle.

[0038]According to the aspects of the present invention, the resin fine particle that is available at a low cost and is used for obtaining resin particles and a toner having sharp particle size distributions and high circularities can be provided. Further, the methods of producing a resin particle and a toner each involving using the resin fine particle can be provided.

Problems solved by technology

However, the inventors of the present invention have investigated the production of a toner based on Japanese Patent Application Laid-Open No. 2009-052005, and as a result, have found that resin particles having a satisfactory particle size distribution are not necessarily obtained.

The inventors have investigated a cause for the foregoing, and as a result, have considered that the resin fine particle used in the approach has a weak affinity for a resin solution and cannot maintain the dispersion stability, and hence a satisfactory particle size distribution is not obtained.

The inventors have investigated a cause for the foregoing, and as a result, have considered that the resin fine particle used in the approach has a weak affinity for carbon dioxide serving as the dispersion medium and cannot maintain the dispersion stability, and hence a satisfactory particle size distribution is not obtained.

In addition, the inventors have formed droplets with reference to Japanese Patent Application Laid-Open No. 2013-137535 while heating the resin solution to reduce its viscosity for the purpose of additionally improving the particle size distribution, and as a result, have found that contrary to expectations, toner particles having a satisfactory particle size distribution are not obtained.

The inventors have investigated a cause for the foregoing, and as a result, have found that the used resin fine particle is deficient in resistance to an organic solvent at high temperature.

As is understood from the foregoing, there still remain problems to be solved for obtaining a toner having a sharp particle size distribution and a high circularity in a method of producing a resin particle involving using a resin fine particle as a dispersant and using carbon dioxide as a dispersion medium.

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